Hey bruv
In my experience, and of Paul C…
There’s very very VERY little chance of any muscle loss at up to 50-70 hours fasting, so if your concerned/paranoid - go with 24-36 hours as a trial, see how you feel.
Sometimes you gotta be your own lab rat and just try shit out. Your a big fella and I bet although parts of the fast will be a bitch, you’ll feel better, look better and have learnt something after.
Please post experience if you give it a shot.
Cheers